Pogo has changed the way unlocking works in Mahjong Escape, at least for the Japan level. Completing one puzzle in the China level will unlock the puzzles in the Japan level, so players no longer have to complete all 60 puzzles in the China level to access the puzzles in the Japan level. At this point, unlocking Early India and Egypt remain the same — you must complete all puzzles in the previous level to access them.
If you haven’t played Mahjong Escape at all, complete one puzzle in China to open Japan. If you have played some but not all puzzles in China, open the game to unlock Japan puzzles as well.